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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?afiA+0MirxS2iqTWECQO1rAhYVCi+wtRmrIMLCyfhRrNy+yP14bytwRh60v6?= =?us-ascii?Q?9I7xa/hmgGjqc16JDfm0yNdzgv8TKDaCxDyx5oDlzfiA1TiKQ+H6dJufVORF?= =?us-ascii?Q?ezIprlY8tdvBb7b+6JvdKKFK8nfzUTBSUOo9LUF8yt5mRqv64TX9BPondfAd?= =?us-ascii?Q?Ke4/ybSDf+dPjZ7WZ6x3sOG7oun0WoAsQW1ZqBFK/CyawTAdYMpoZQ2uUkGZ?= =?us-ascii?Q?pzawVcEURy/EE/hgT686FzW4zo+mCljTV6auOjYtPqfKh2zTq217Q67j+J/k?= =?us-ascii?Q?1OJadZ+KNlo8amNZyr5Onq9NuYaAL+/FiUJGd1ZYkv2AGT/xVCVCISRcX669?= =?us-ascii?Q?lSgs4p3lr/5yfW2gvg5tyXDh9mgoXfGZIs162SZWmKDPujSVSdNsZTSem5nC?= =?us-ascii?Q?zZF9sSjtvQnHSeZSkHSNnKoA0aXWsSHHA0+bXv6UR4Wto1iHzj+UfL1OE7/i?= =?us-ascii?Q?L7ClZ83UbCfulHQG/jBiPBbJeqQeOklxoAuEPDtabedQtGyO9H5XCKfNKsVL?= =?us-ascii?Q?jOKOC6elyF1mlX3RrKmg3/EQaWDVTj2BEjTfhlu4cG8tD6iGEcLtqAvb3gLx?= =?us-ascii?Q?4Ffk6qpjXw6+3D1Hl2b9dQh+5MYwwfJVIREGU0fvz/qqa71RWHKMoi27efgE?= =?us-ascii?Q?vOpV288aZ9hKyOHOwXuFTU3uXKRiu7efKWMgHUOdToZvcQ5OlmDkn6srAwQw?= =?us-ascii?Q?VNiv2Wm0QSwzgX6FiZSHwO21qnCDG0HEj/J5NWywrtry4+sSxhvZqX9hQBgP?= =?us-ascii?Q?89dl55NmpZC4lMnBbu7rqOpP1GiJkpP7gNYLbCqBXURLKyYPmlV8n+B4q+wu?= =?us-ascii?Q?oSntD5P7PQ+KjGK/iKIXQusTZtsanqECm81KyKGNeE/IDZ0HqsMuWsMcWJuC?= =?us-ascii?Q?h4QRQje5HpBHsWiqGdLf2PDtZOFFU8oqIUlYqDDTHDE2mOehPBX17/czX1LJ?= =?us-ascii?Q?nUwxCsqupqXYKYTj/VnhvU6C53ffStleLAW4xzAyyj5jgh3SXW5JIqwWpR8f?= =?us-ascii?Q?yZ/YqSl1MwBLqk9jlHkESIUcolGl3TQjJgmL/OtYwqredBondGWkRnB1VXAn?= =?us-ascii?Q?p1thJF+8z1eW1Nl24Qyu02tIOFR1dR5nEBnOLHJp49y32Yot9vSHXDZo8S4e?= =?us-ascii?Q?llp9ptHIDDBf/6S6dIiHiiopgxhj27xEm0QxyETpx4ea3VpYcyQShB8Z7M/X?= =?us-ascii?Q?YDIDbrNHAlr9bdH6E9BgL5D+TxXVgyL4Cg6w85PcttHChdbTtGDwtscd2lct?= =?us-ascii?Q?vYlFXfMx0kouIrMjIEkAq0o7XtFQgpAUYsd6DVGZa/xKY1tG8AXaD5wZcPrB?= =?us-ascii?Q?Wy1PjcRxrU7jv/+WSdfjByHeGgx4bgX4n32E8sEH3PDWmZm2noTjSvqCzkDF?= =?us-ascii?Q?4CRMXtRnq7Hk4BNBKXtztLvalMunaK+6eoX7OSwmXBfdKIcceZ+ciJy1RMyn?= =?us-ascii?Q?TSndFSqFnTLQVErfxzW9npc/FiutOvV1TiAS+NDHeBUEby2y8FyN0+/tem3g?= =?us-ascii?Q?54fqAmG++yoWnVt702RjyH9f7wkP7SueQ1YfAKV7MzQbe4/dvGsggi01on/H?= =?us-ascii?Q?QMUwc0ZrT0znYCIRuBaHB5Nh2rW8XJ6rRs/3gBSGDRDNN9m79D1TS6hckG50?= =?us-ascii?Q?6PDE7RmMOK7W3WwC+RlTGRXik98/UXxaBOzVEz10HrkOkQoaMG7tGaUd46/I?= =?us-ascii?Q?eXrJdEHHwMrZ/SMMveiMR3Njx8Zzxe8dUM0wXHxKpsOgULOR?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b224616d-34bd-4583-d00f-08df0a8ef7b2 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Sep 2026 14:15:26.9288 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: KIplqGmouBkyhgcDk/+8OaYt9zly9KHSSEfrLWFTs33++foTK0tBR5jmDbbCO5HG X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8210 On Thu, Sep 03, 2026 at 12:18:33PM -0700, Jonathan Cameron wrote: > > arm_smmu_setup_irqs() has three failure paths that leave the priq without > > a handler: a missing priq IRQ line, devm_request_threaded_irq() failure on > > the priq IRQ, and devm_request_threaded_irq() failure on the combined IRQ. > > Each path warned but kept ARM_SMMU_FEAT_PRI set in smmu->features. > > > > With FEAT_PRI still set, arm_smmu_setup_irqs() enables IRQ_CTRL_PRIQ_IRQEN > > against a handler that does not exist, and a later change would then have > > arm_smmu_probe_device() call pci_enable_pri() on PCIe endpoints, allowing > > them to issue PRI Page Requests that pile up in the priq with no drainer. > > Separately, arm_smmu_device_reset() has already enabled CR0_PRIQEN before > > it invoked arm_smmu_setup_irqs(), so the hardware queue would stay enabled > > regardless of what setup_irqs decides. > > > > Clear ARM_SMMU_FEAT_PRI in all three failure paths, so that subsequent code > > treats PRI as unavailable. And disable CR0_PRIQEN after the setup function > > returns. > > > > A kdump kernel cannot service page requests: strip FEAT_PRI when detecting > > features, so downstream PRI setup is skipped. > > Dumb question - why can't a kdump kernel service page requests? > I'm nowhere near familiar enough with that stuff and I suspect I'm not > the only one who might be in that state and reading this series. > Configuration choice, or a fundamental thing? The initial issue is the streams are left in whatever state the crash kernel had them in, so it can be generating a bunch of PRIs with no place to put them. Though eventually we may find a device where dropping them is not good and they need to be NAK'd promptly.. But I think the real motivation here is to save memory in the kdump kernel.. Jason